For the love of god, how do you do the right hand rule?

[mrh125]

I'm very left-handed and probably mildly dyslexic because of it. Half the time I can't do the right hand rule right. It's frustrating me so much lol. It's the cross product one with the F=qXV. Is there any easy way to do this without making me dislocate my wrist to get a wrong answer or skip using my hand?

I also sometimes get totally whacky answers that make no sense using my hand.

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[ashtonjam]

Do you mean the magnetic force, F = qv x B?

Start with your fingers on your right hand extended straight in the direction of v and with your right thumb at a right angle to the rest of your fingers making the L shape. Then, you have to find a direction in which you can curl your fingers so they line up with B. Your right thumb gives the direction of the force.

This is the left side in the picture below. In this case, v is pointing straight up, so point your fingers up. B is to the left, so your fingers should curve to the left (your right palm points left to make this possible). Your thumb sticks directly out of the screen towards you. The right-side method in the picture also works well.

 

[mrh125]

Do you mean the magnetic force, F = qv x B?

Start with your fingers on your right hand extended straight in the direction of v and with your right thumb at a right angle to the rest of your fingers making the L shape. Then, you have to find a direction in which you can curl your fingers so they line up with B. Your right thumb gives the direction of the force.

This is the left side in the picture below. In this case, v is pointing straight up, so point your fingers up. B is to the left, so your fingers should curve to the left (your right palm points left to make this possible). Your thumb sticks directly out of the screen towards you. The right-side method in the picture also works well.

Yes, that thing. I don't understand the curling either. Also I have serious trouble trouble if you have the magnetic field or velocity going into or out of the board.

 

[ashtonjam]

Yes, that thing. I don't understand the curling either. Also I have serious trouble trouble if you have the magnetic field or velocity going into or out of the board.

If the curling isn't making sense, you can try doing the palm method on the right side of that picture. Using that style, the thumb goes towards the first vector in the cross product (velocity = thumb), and then all of your other fingers go towards the second vector in the cross product (magnetic field). Then your palm points in the direction of the magnetic force. There's a lot of ways to do this and it might take some trial and error before it sinks in 😉

EDIT: If the velocity is coming out of the computer screen, for example, then you point your right thumb towards your nose. Then, the way you point your other fingers depends on the direction of the magnetic field; you swing your fingers around to match the direction of the magnetic field while keeping your thumb still as the axis of rotation. If the magnetic field is pointing upwards within the plane of the screen, your fingers point up so you're doing this:

Then, your palm points in the direction of the magnetic force. In that picture, the guy's palm is pointing in the direction of the force since that's his right hand. It takes some playing around with it to get more complicated angles.

 

[mrh125]

Thanks I got so much better now I think 🙂.